Noise shield for handsets



March 29, 1949. P. s. VENEKLASEN NOISE SHIELD FOR HANDSE'IS Filed Jan. 29, 1946 Patented Mar. 29, 1949 PATENT 01F F 1 CE iNOI'SE SHIELD FORHANDSETS Paul 238. iiveneklasen, E South "Pasadena, Galiii, asa'signonto the United States of-America as represented .by .the-,Executive..Secretary .of. the Ofiice .ofiscientific:Research and Development Application January 29, 1946, Serial No. 644,008

5 Glaims. 1

This invention relates to 'telephone handsets.

An object of 'the-inventionis'toimprove-the operation of telephone handsets *and to devise a noise shield member for-excludingzambient noise -during'the operation of a handset. :Anotherom vject of the invention is to providaa noisershield member which is soconstructed-as to'permit :substantially sealed engagement of this member over 'the-i'ace of 'the user and to maintaining 'this -s'ealed relation during speech. Other objects and:

novel features will appear from the following description of the invention.

In the-accompanying drawings: Fig. 1 is a view inside elevationzand partial cross section illustrating-a hand telephone awith the noise shieldof the-invention mounted thereon; A and Fig. 2' isa frontelevational view,- partly in cross section.

The-noise shield of theinventio'n generally inv cludesacup-shaped member-adapted 'to fit about the *face and "means for flexibly supporting this .memberin various positions of "angularity'relative to the face ofthe user during-speech.

Considering the "structure showm in the "drawings, numeral 2 denotes airamemembenfor a telephone handset. The frame is'of tubular construction and'its middle portion-is=:provided with a conventional switcharrangementoperated by meansoi a switch button kpartly'recesse'd' in the frame member at the' inner side thereof. Numer- ;al-.6 denotes an earphoneat'the upper end of" the frame member, and numeral '8 denotes a base portion ofthe ,frame to whichthe"noise-shield Ihody element ;9 of the invention is attached. Thisbody includesseveral integral instrumentalities for the application and functioning of the device, as will be more specifically 'd'escribed hereinafter.

The noise shield member is cup-shaped as .shown in Fig. 1, having curved o'uterfront edges for engaging against the face -of 'a'person and .forwarclly diverging side walls denoted by the numeral I6 and constituting part of a voice chamber I I. Preferablythe noise shield-'inembei" -is composed of moderately softrubber or rubberlike material such as neoprene. Other suitable substancesmay'beemployed. At the lower-or ;rear'end of thebo'dy element 9, I have provided a cylindrical'webbing or tube 22 which is'an integral continuation of the side walls and has iormed on the innerssidethereof extending ;on "tothe right and left walls of the voice chamber I'I two longitudinal rib portions 26, through :which are formed respective alr'passages l8. Thecylindrical webbing 22, at its lower end, terminates tin a hollow base or .neck part 19 of reduced diameter, open rearwardlyandhaving an integral "interior terminal :nec-k 2! of further-reduced *diametentopermit its engagement and fit around anupper reduced part of the base 8 of the frame member. The base is terminally shaped and "channeled circumferentially so as to receive the neck 2| as shown in the drawings, and so Fpresents an outwardly projecting ridge 23 which is fitted within the neck l9 andagainst the forward side of the'neck 2i.

Numeral l4 indicates a biscuit shaped microphone which is snugly supported in a socket member 15, in turn integraland concentric with the'tube 22 and suspended therewithinior moderate universal pivotal or translative movement *ofthe socket relative to the base 8, in the manner more clearly indicated in Fig. 2 where a thin planiform annular wall 24 normal .to the axis of'the tube is the joining part. As will 'be observed from an inspection of this figura'the annular bottom or microphone seat [3 of the socket member I 5 occurs in spaced relation with respect "to the plan of a planiform bottom flexibleannular planiform wall'2-6 formed on the rear-end of the'tube 22 and joining the latter to the neck 19-01 the annular webbing 22, thus supporting the socket member in a highly-flexible manner -so that movement of the upper portion of;the noise shield, including the sidewalls, 16, together :with the microphone l4, may occur relative to "the base portion of the frame 8. Electrical conductors, I2, extending through a passageway, 10, in the frame, '8, project upwardly and :are

connected at the under side of the microphone, .as shown in Fig. 1. to move with the microphone and upper portion These wires are adapted of the noise shield 'when' displacement occurs.

It'should be noted that the ribs and passages 18 extend a substantial distance .iorwar'dly be- "yond the socket member l5 and in use arelo- *cated laterally of the mouth of the user. .They went excess air -from=within the shield member, 50 asto avoid lnterference with utterances of 3 the user by back pressure in the voice chamber, and they are small enough to attenuate sound passing therethrough so that voice sounds escaping will be faint. Their indirect relation to the path of sound originating in the larynx of the user will in addition result in great interference'between, and damping of, sound waves gaining access thereto, so that no words uttered within the device will be distinguishable by a nearby person. Since the facial surfaces of the user which close the forward side of the voice chamber I! are sound-absorbing, and sincein phase Waves of original speech sounds 'gaining-- access to the vent passages l8 must be reversed in direction, principally by components of reflection from facial surfaces, out-of-phase echoes in the voice chamber which are immaterial in affooting message reception at the microphone are of amplitude which is substantial in relation to that of in-phase sound waves reaching the passages l8, and so interference will contribute further to making escaping sound components of speech indistinguishable.

Due to the nature of the material of the body 9, the planiform wall 26 is extremely flexible so that the whole shield and microphone as a unit are easily rockable in any direction on the base 8, and the shield will consequently become automatically adjusted to various angular. positions, according to the peculiarities of various faces or the mouth adjustments desired at different times by a user. In addition, there are permitted angular movements of the shield unit freelyin relation to the base, incident to movements of the chin of a speaker using the device. It will be seen in Fig. 2 that the wall parts I6 at top and bottom of the mouthpiece or voice chamber are thinner than the wall parts l6 at the sides of the voice chamber.

This permits the user to articulate more freely, avoiding impedance of oral motions. While the lower wall part I6 will move principally, incident to ordinary mouth movements, depression of this part will produce a slight rocking of the shield and microphone downwardly as a unit, and the upper part l6 will flex slightly to permit and respond to such rocking without objectionably pressing vertically downwardly on the upper lip of the user. H

The rocking of the unit as stated will result in always presenting the microphone toward the speaker in such position as to most efiiciently respond to voice utterances-that is, in planes closely approximating the normal in relation to the mean directions of the voice waves at various positions of the mouth relative to the base 8.

At the same time, throughout all positions of the shield device relative to the base frame 8, the microphone is floatingly supported by the web or wall 24, so that it is in some measure translatively movable by its inertia within the tube 22 when the shield is subjected to concussions or blows. The air space surrounding the socket l5 within the tube 22 will reduce the force of impact of shock waves from explosions.

It will thus be seen that the noise shield is so designed that it may be used by individuals having unusual variations in facial size and contour. Moreover, it is so flexibly mounted with respect to the base of the frame that it yields readily to facial motions required in speech articulation. These two features combine to make the device extremely comfortable and exceedingly eflicient. The air passages, l8, permit the breath to escape While speaking. These openings are 4 designed as to have a minimum effect on the acoustic insulation provided by the noise shield. It is intended that the flexible mounting of a microphone relative to a supporting base may be carried out with other forms of supporting structures than the particular flexible webbing .describeds. Similarly, it ;is;intended that the arrangement of a ductile mounting for a. microphone may be combined with other types of supporting members.

While I have shown a preferred embodiment of my invention, it should be understood that various changes and modifications may be resorted to, in keeping with the spirit of the inopen microphone-receiving socket member on said inward extension constructed to fit around a microphone unit, said socket member in spaced relation to said tube and to saidmeans for connecting said cup-shaped member to the said base,- and having an integral annular microphone seat at its rear part.

2. An integral combined noise shield, and shock absorbing mount for microphones in telephone sets, comprising a body of elastic highly flexible material having a hollow base neck open at the rear part of the body constructed to elastically 40 receive and bind upon an inserted base frame member, said body having a planiform flexible wall extending outward from said neck-normal to the axis of the neck, and having an integral cylindrical coaxial tube extending forwardly therefrom, flared at its forward portions to form a voice chamber and mouth-piece generallyconforming to contours of the face of a person, a

: second planiform cylindrical wall spaced forrearwardly from said voice chamber so .as to support an engaged transmitter unit in spaced rockable relation to an engaged base.

3. A sound shield and shock absorbing mount for microphones in telephone sets, comprising a body of elastic highly flexible material having a voice chamber open to receive therein and conform to a portion, of the face of the user, a microphonesocket integral with said body constructed to elastically fit around and support a microphone and having an integral lateral annular substantially planiform wall normal to the'axis of the socket spaced Within and joined toa rearward part of said body whereby to support, a microphone. in the socket yieldingly for universal movement relative to the other parts of said body, said body having a tubular highly flexible part extended rearwardly around and in spaced relation to said socket, shaped for securing engagement with a support whereby said tubular part constitutes a spaced protective wall spaced around the socket and a universal pivot coupling between the support and the parts of said body forwardly of the support.

4. The structure of claim 3 wherein the wall of the voice chamber is extended continuously rearward in the form of a non resonant highly flexible elastic tube shaped and constructed at its rear extremity to fit snugly around a support to secure the device on such support and seal the rearward end of the tube, said lateral annular wall continuously circumscribing said socket and continuously joinedto said tube whereby with the seal at the support and the fit of the socket upon a microphone, an enclosed air space is formed surrounding the microphone at the sides and rear.

5. The structure of claim 3 wherein the rearward end portion of said tubular part is formed with a thin-walled neck, and a thickened second farther neck of further restricted diameter, and

a handset member including a base having a part to fit snugly in the neck and having a channel part to snugly receive the said second neck.

PAUL S. VENEKLASEN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,368,261 Jenkins Feb, 15, 1921 1,440,752 Stone Jan. 2, 1923 15 1,757,463 McCann May 6, 1930 1,930,906 Nordenswan Oct. 1'7, 1933 2,121,941 Wurdel June 28, 1938 2,226,959 Zimmerman Dec. 31, 1940 2,390,488 Alford et al Dec. 11, 1945 20 2,398,076 Bulbulian .d Apr. 9, 1946 2,408,474 Newman et a1. Oct. 1, 1946 

